000
WTPZ42 KNHC 192045
TCDEP2

HURRICANE PAINE DISCUSSION NUMBER   8
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP172016
200 PM PDT MON SEP 19 2016

Visible satellite imagery shows a ragged 20 nm diameter eye
appearing in Paine's central dense overcast.  Infrared imagery does
indicate quite vigorous thunderstorms, but with a somewhat
asymmetric structure with the coldest cloud tops only observed in
the western semicircle. The slightly stronger initial intensity of
80 kt is a blend of a 77 kt subjective Dvorak estimate from TAFB and
a 90 kt value from ADT.

Given that Paine is now traversing sub-26C waters while experiencing
moderate southwesterly vertical shear, one would expect that it has
reached its peak intensity.  But given this somewhat surprising
hurricane, this is not guaranteed.  As Paine turns toward the north
or north-northeast over the next two days, it will move over even
colder SSTs, through a stable atmosphere, and into higher shear.
Thus the NHC intensity forecast shows a rapid weakening - 35 kt in
24 hours - with Paine becoming a remnant low in 48 hours, or
sooner. This forecast is based upon a blend of the tightly clustered
members of the IVCN intensity consensus technique, and is nearly the
same as that from the previous advisory, despite the higher initial
intensity.

Paine is moving toward the northwest at 14 kt, steered between a
deep-layer ridge to its northeast and an upper-level cut-off-low to
its northwest.  The tropical cyclone should recurve to the north in
about a day and then decelerate as it encounters a weak low-level
steering flow near northern Baja California.  The NHC track forecast
is between the previous advisory and the TVCN multi-model track
consensus.

A 1658Z ASCAT-B scatterometer pass showed that Paine was slightly
larger in its 34 and 50 kt wind radii than previously indicated.
The NHC wind radii forecast is based upon a blend of the larger
climatology/persistence model - DRCL - and the smaller multi-model
consensus technique - RVCN.

Deep-layer moisture associated with Paine or its remnants is
expected to spread over portions of the northern Baja California
peninsula of Mexico and the southwestern United States during the
next day or two.  This could enhance the rainfall potential in these
areas.

Even though the official forecast does not have Paine making
landfall as a tropical storm, the system will move close enough to
the west coast of Baja California that tropical-storm-force winds
are increasingly likely.  Thus the Government of Mexico has issued a
Tropical Storm Warning for portions of the northwestern Baja
California peninsula.

FORECAST POSITIONS AND MAX WINDS

INIT  19/2100Z 22.8N 116.2W   80 KT  90 MPH
 12H  20/0600Z 24.7N 116.8W   70 KT  80 MPH
 24H  20/1800Z 26.9N 116.9W   50 KT  60 MPH
 36H  21/0600Z 28.8N 116.3W   35 KT  40 MPH
 48H  21/1800Z 30.1N 115.7W   25 KT  30 MPH...POST-TROP/REMNT LOW
 72H  22/1800Z...DISSIPATED

$$
Forecaster Landsea/Stewart